Disclaimer: The following material is being kept online for archival purposes.
Although accurate at the time of publication, it is no longer being updated. The page may contain broken links or outdated information, and parts may not function in current web browsers.
CME-Driven Solar Wind Disturbances Far From the Sun and at High Latitudes
John T. Gosling
Ulysses has observed a large number of CME-driven solar wind disturbances
during the rise of the present solar activity cycle. Indeed, the
number of transient events identified in the Ulysses data set far exceeds
that previously identified at large distances in the Pioneer 10 and 11
and Voyager 1 and 2 data sets. These disturbances are usually best
identified by counterstreaming fluxes of suprathermal electrons in pitch
angle plots of the Ulysses plasma data. The prevalence of counterstreaming
indicates that even at large heliocentric distances a large fraction of
the magnetic field lines threading most CMEs are rooted at both ends in
the solar corona. Most CMEs at large distances have distinct magnetic
field signatures, although these signatures vary from event to event and
one often can not identify a CME on the basis of the field signature alone.
Most of the CMEs do not fit the standard definition of magnetic clouds,
although some magnetic clouds are clearly present in the data. A
number of the CMEs drive shock wave disturbances, but at large distances
the shocks usually are relatively weak, and most CME-driven disturbances
at distances of 3-5 AU do not provide large perturbations to the solar
wind speed. Many of the CMEs at large distances have very large spatial
extents owing to their expansion en route from the Sun. Here we provide
an overview of these disturbances as identified by the solar wind plasma
and magnetic field experiments on Ulysses.
Authors: J. T. Gosling, D. J. McComas, R. M. Skoug, and
R. J. Forsyth
Organization: Los Alamos National Laboratory
Address: MS D466
Los Alamos, NM 87545
Above is background material for archival reference only.